FJ40 2F Exhaust Manifold Gasket Question (1 Viewer)

Joined
Jan 1, 2011
Messages
61
Location
Tempe, Arizona
I know some of this has been covered before, but at the risk of being beat upon, let me re-inquire and add another related question:

1) I purchased one of the 1/8" thick graphite Intake/Exhaust Manifold Gaskets from SOR. I don't think the list it anymore because I can't find it on their site, at least not for a '78 FJ40 (It was a 044-01C which is supposed to be for the later model FJ40's)

So the holes on that gasket look like the one below. Notice that the openings don't have any seal between center exhaust cylinder ports. My question is, IS THAT A PROBLEM? The think gasket that came with the headers has gasket has a seal between those ports, but this one leaves them open. I notice that SOR is selling a new Aftermarket Gasket for the later model 2F engine that looks exactly the same (on the right). Should I assume this suggests it fine? Do you lose any power with this opening or does damage the pipes in anyway?
I prefer to use the thick gasket, but I can always use the thinner one if that will be better.\

2) The redundant question involves whether to use a copper sealant or not? I know a lot of folks say to use it. Can I just ask one last time for advice, and what to use if you recomment it? I've had that intake and exhaust faces surfaced so they should seat pretty flush.

Thanks for the advice!!

1607302459011.png
1607303854640.png
 
Joined
Jan 1, 2011
Messages
61
Location
Tempe, Arizona
Remflex gasket


So, this is the same hole sizes, so I assume you are saying that presents no issues, correct?

Other than this is nearly a $50 gasket, I don't see what makes it superior to the 1/8" graphite gasket from SOR that I paid $30 for. They look to be about the same thing. Appreciate the comment, but I wish I understood what this one was so much better.

I did note that Remflex doesn't recommend using sealants. I thought that was interesting.
 
Joined
Feb 3, 2020
Messages
255
Location
Stanwood, WA
I have used Remflex on the headers on my big block Chevy motor and various small blocks and they seal awesome and don’t come loose. One will be going on my F when I get there.
I am not yet familiar enough with the valve timing on the F to know but I don’t think the open space would hurt anything. The only issue you could really run into is 2 exhaust valves being open at the same time and cause a problem. But, both exhaust valves open should mean exhaust gasses are pushing out so they’d both be going down the hole. Only time there’d be a problem is with one valve expending gasses and the other valve letting them be sucked in. But in that scenario, you’d have a much bigger problem than a gasket.
So ya.... remflex and forget it!
 
Joined
Jan 1, 2011
Messages
61
Location
Tempe, Arizona
I’m also replacing some of the connections on the intake manifold. What is the proper thread sealant for that application?
 
Joined
Jan 1, 2011
Messages
61
Location
Tempe, Arizona
I know some of this has been covered before, but at the risk of being beat upon, let me re-inquire and add another related question:

1) I purchased one of the 1/8" thick graphite Intake/Exhaust Manifold Gaskets from SOR. I don't think the list it anymore because I can't find it on their site, at least not for a '78 FJ40 (It was a 044-01C which is supposed to be for the later model FJ40's)

So the holes on that gasket look like the one below. Notice that the openings don't have any seal between center exhaust cylinder ports. My question is, IS THAT A PROBLEM? The think gasket that came with the headers has gasket has a seal between those ports, but this one leaves them open. I notice that SOR is selling a new Aftermarket Gasket for the later model 2F engine that looks exactly the same (on the right). Should I assume this suggests it fine? Do you lose any power with this opening or does damage the pipes in anyway?
I prefer to use the thick gasket, but I can always use the thinner one if that will be better.\

2) The redundant question involves whether to use a copper sealant or not? I know a lot of folks say to use it. Can I just ask one last time for advice, and what to use if you recomment it? I've had that intake and exhaust faces surfaced so they should seat pretty flush.

Thanks for the advice!!


View attachment 2517607View attachment 2517637
1607462847082.png


Postcscript:

Turns out this graphite gasket from SOR (above) was made from a Treadit GR1661 material. While it is appropriate for an exhaust application, Treadit doesn't make Exhaust gaskets as a normal course of business (from what I can tell), so this was probably made to (and for) SOR Specs.

I took the advice above and ordered the Remflex graphite gasket. At least you know you are buying a gasket that was manufactured by a company specifically for the application for which you are using it. Many thanks to guys who commented.
 
Last edited:

dlzadl

SILVER Star
Joined
Aug 13, 2012
Messages
386
Location
Akron, OH
Follow the remflex torque specs and the torque sequence in the fsm. Not as tight as you would think
 

Steamer

SILVER Star
Joined
Jul 20, 2009
Messages
1,492
Location
Miami, FL
One will be going on my F when I get there.

Something to consider when using a Remflex on an F or F.5. Remflex makes only one gasket that covers the F, F.5 & the 2F. Years 68 through 87. With the smaller studs or bolts on the F & F.5, you get a little slop with the larger holes. I found this out after I bought one. I did not use it and got an OEM. Toyota does not seem to mind making two different gaskets with the corresponding stud hole size.
 

Steamer

SILVER Star
Joined
Jul 20, 2009
Messages
1,492
Location
Miami, FL
@Steamer why do you want to send this guy spinning down the rabbit hole?
Sorry, I thought I was clear with my quote. I was replying to Skreddy who said he was planning on putting a Remflex on his "F". I was simply pointing out that the gasket holes will be a bit sloppy on the smaller studs of his F. It won't matter to the OP with his 2F and the larger studs.

Great pic btw
 
Joined
Feb 3, 2020
Messages
255
Location
Stanwood, WA
I’m used to a sloppy fit... If the bolt holes in the gasket are too big, just snug it down with a little movement, line it up and finish it off. I haven’t seen the actual gasket yet, but the ports are usually slightly oversized so the difference in hole size for different stud diameter shouldn’t really matter. But I usually line up all gaskets on the head and exhaust and on intake anyway to check for core shift; something learned from dealing with BBC motors.
 
Last edited:

Steamer

SILVER Star
Joined
Jul 20, 2009
Messages
1,492
Location
Miami, FL
I guess it sticks in my mind from when I first got my rig 20yrs ago. Napa sold me a 2F gasket by mistake and I did not even know what a 2F was. But the slop of the bigger holes made the difference. Even though I had the manifolds planed, the hole slop gave me exhaust leaks at the bottom. When I figured it out, I simply raised the gasket up on the slop and jammed the manifolds in to hold the gasket up there till the nuts were snugged up. It stopped the leaks. I thought it was the result of sloppy aftermarket gasket making but It was years later I found out the 2F studs were larger. I guess it was that experience that bugged me that Remflex could not make two gaskets to cover the two stud sizes. Not a big deal but I thought it was something the F guys should take note of.
 
Joined
Feb 15, 2016
Messages
377
Location
Somerset KY
I’m also replacing some of the connections on the intake manifold. What is the proper thread sealant for that application?
ptfe paste or Teflon tape (wrapped in the correct orientation) NOTE: All threads on FJ40 "pipe fittings" are bspt/metric. The bspt and metric are identical in thread geometry, with the metric having a chamfer on the leading edge.
 

Users who are viewing this thread

Top Bottom